Cat Scratch Disease

Cat Scratch Disease (CSD) is an infection caused by bacteria called Bartonella henselae. Domestic cats carry the CSD bacteria, which are transmitted between cats by fleas. People can get CSD when feces from an infected flea enter a wound or break in the skin, often following a bite or scratch from a cat. In healthy people, CSD is most often a mild illness characterized by one or two swollen lymph nodes. More severe disease, including infection of the heart, may occur in persons with weakened immune systems.

About 40 percent of cats carry the CSD bacteria at some time in their lives, with young cats and kittens being more likely than older cats to be infected. Cat owners can reduce their risk of CSD by washing their hands after handling, petting, or playing with a cat, by adopting older (> 1 year) cats, and by maintaining a flea control program.